Skip to main content
cancel
Showing results for 
Search instead for 
Did you mean: 

Find everything you need to get certified on Fabric—skills challenges, live sessions, exam prep, role guidance, and more. Get started

Reply
OwenA
Frequent Visitor

Standard Deviation by Group

Hi and thank you in advance,

 

Big Picture: I need to create a flag that tells me when a value exceeds 95% confidence interval (the accepted tolerance limit in this case). These flags will then be counted and reported about by hierarchical group (city, state, country for example) so individual managers can investigate why those exceed expected parameters. 

Technical Issue: I'm having difficulty calculating the standard deviation by row by hierachy group.  

 

OwenA_0-1682959046618.png

The formula used in "desired standard deviation" column is stdev.p(if($A:$A=$A2,$B:$B)).

 

How do I replicate this in Power BI?

 

Thanks so much for your help.

 

Owen

 

P.S. Bonus cool points if your solution can be extended to other math functions. 

1 REPLY 1
johnt75
Super User
Super User

You could create a summary table like

Summary Table =
SUMMARIZECOLUMNS (
    'Table'[Bucket],
    "Average", AVERAGE ( 'Table'[Value] ),
    "Std Dev", STDEV.P ( 'Table'[Value] )
)

and then link that to your main fact table. You would then be able to create columns on your fact table which refer to the summary table, e.g. 

Flag =
IF (
    'Table'[Value]
        > RELATED ( 'Summary Table'[Average] ) + RELATED ( 'Summary Table'[Std dev] ),
    1,
    0
)

Helpful resources

Announcements
Europe Fabric Conference

Europe’s largest Microsoft Fabric Community Conference

Join the community in Stockholm for expert Microsoft Fabric learning including a very exciting keynote from Arun Ulag, Corporate Vice President, Azure Data.

Power BI Carousel June 2024

Power BI Monthly Update - June 2024

Check out the June 2024 Power BI update to learn about new features.

RTI Forums Carousel3

New forum boards available in Real-Time Intelligence.

Ask questions in Eventhouse and KQL, Eventstream, and Reflex.